How to Flare Aluminum Tubing

Soft aluminum tubing, used for HVAC connections in your home and vehicle, employs a compression fitting to seal joints between lengths of tubing and fittings. A compression fitting consists of a female threaded end and a male threaded connector. To use the compression fitting with aluminum pipe, you need to use a flaring tool to flare the end of the aluminum tubing. The flared section of the aluminum tubing will then seat against the tapered end of the threaded male section of the compression fitting, sealing the connection.

Step 1

Cut the soft aluminum tubing to the length you need with a tubing cutter. Cut the tubing slowly to ensure that you do not dent or shrink the end of the aluminum tubing.

Step 2

Disassemble the compression fitting and insert the aluminum tubing into the female side of the compression fitting. Make sure that the female threads of the fitting are facing toward the end of the aluminum tubing that will be flared.

Step 3

Open the flaring vise per flaring tool operating instructions, and place the aluminum tubing in the hole of the vise that fits the outside diameter of the aluminum tubing.

Step 4

Tighten the holding vise of the flaring tool, while holding the end of the aluminum tubing flush with the outside edge of the vise, and slide the flaring tool over the flaring vise.

Step 5

Turn the handle of the flaring tool clockwise to push the cone on the end of the flaring tool into the end of the aluminum tubing.

Step 6

Continue turning the handle of the flaring tool until the flaring tool bottoms out against the flaring vise.

Step 7

Turn the handle of the flaring tool counter-clockwise to remove the cone of the flaring tool from the flared end of the aluminum tubing.

Step 8

Loosen the holding vise and remove the flared aluminum tubing from the flaring vise.